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Lassen County, CA Weather Forecast
Lassen County, CA Weather Forecast Date: 232 PM PST Mon Mar 02 2026
The area/counties/county of: Lassen, including the cities of: Portola, Susanville, Westwood, Sierraville, and Loyalton.or toggle through each period.
Tonight... Clear. Patchy fog after midnight. Lows 26 to 36. Northwest winds around 10 mph in the evening becoming light.
Tuesday... Sunny. Patchy fog in the morning. Highs 58 to 63. Light winds becoming south around 10 mph in the afternoon.
Tuesday Night... Partly cloudy. Lows 28 to 38. Southwest winds around 10 mph in the evening becoming light.
Wednesday... Chance of rain and snow. Snow level 6000 feet. Highs 45 to 55. Light winds becoming west 15 to 20 mph with gusts up to 35 mph in the afternoon.
Wednesday Night... Mostly cloudy with a chance of snow and rain in the evening, then partly cloudy after midnight. Snow level 5000 feet lowering to the valley floor. Lows 22 to 32. Northwest winds 10 to 15 mph. Gusts up to 35 mph in the evening.
Thursday... Partly cloudy. Highs 42 to 52.
Thursday Night... Clear. Lows 21 to 31.
Friday... Clear. Highs 46 to 56. Lows 25 to 35.
Friday Night... Clear. Highs 46 to 56. Lows 25 to 35.
Saturday... Clear. Highs 57 to 62. Lows 29 to 39.
Saturday Night... Clear. Highs 57 to 62. Lows 29 to 39.
Sunday... Sunny. Highs 59 to 69.
Sunday Night... Partly cloudy. Lows 30 to 40.
POP = Probability of Precipitation
Lassen County Radar Loop
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